The speed control that I am using with my Hacker C40 is not working correctly. It is a Jetti speed control that was provided with C40 when I bought the package.
The speed control works the motor fine, but after a slight amount of time working the control surfaces, it appears that powe that is going to the servos is depleted (servos work slowly, and eventually stop), but the motor control is still ok.
It almost seems like the voltage regulator is gong bad, if you stop working all the surfaces for a few seconds that surfaces will work ok, then fail slowly.
My battery is fully charged, and the speed control has been working fine for about 2 months.

All the surfaces are free, as I said the plane has been flying fine for 2 months. The surfaces will function fine until you start moving all of them at once. While moving them all at the same time, and after about 5 seconds you can see them slow down then they will get to a point where they are moving so little that it looks as if you were to have a flight pack battery that the battery would be going dead.
I can also feel a component getting warm(real warm not to hot to touch) in the speed control under the heat shrink.

Tom,
Like Greg said, it still sounds like a servo problem. One of oyur servos is pulling too much current. Try this, unplug one servo and test again. If it still has a problem go to the next servo and try again. Repeat with all servos and one should show up as a problem.

That kind of sounds like the problem some of the E3D guys are having with the BEC in the ESC being overworked by too much servo current draw and shutting down. Happens mostly during 3D flying, slamming/holding everything cranked over at extreme throws, sometimes stalling one or more servos. There is a section over in the second E3D building thread that this gets discussed. I had this happen to me a few weeks ago on my E3D and nearly lost the plane over it. I installed a UBEC, rolled my throws back a little bit, and have been trouble-free since.
Which Jeti ESC is it? Some of them are somewhat current limited for the BEC side.